Radio base mounting unit or similar article



FIG. 1 is a front, top and right side perspective view of a radio base mounting unit or similar article showing my new design with the broken line radio shown for illustrative purposes only and forming no part of the claimed design;

FIG. 2 is a left-side elevational view thereof;

FIG. 3 is a rear elevational view thereof; and

FIG. 4 is a bottom plan view thereof. 

The ornamental design for a radio base mounting unit or similar article, substantially as shown and described. 